Conventionally, technology has been disclosed for evaluating performance between client servers (see, for example, Japanese Laid-Open Patent Publication No. 2003-8648 and Japanese Laid-Open Patent Publication No. H9-62601). For example, upon system transitioning, technology that evaluates and tests performance to quickly and accurately verify a standby system server is demanded. Conventionally, such technology has performed processing as described below.
FIG. 22 depicts an example of relative performance evaluation processing for a main system server and a standby system server. In the example depicted in FIG. 22, a main system server A and a testing terminal C are located in Osaka, while a standby system server B is located in Tokyo. The main system server A, for example, is a computer of a system that is in use and operating on a current system. The standby system server B is a computer to which transition will occur from the main system server A. In this case, when testing using identical patterns (a packet and the acknowledgement packet thereof), the test conductor uses the testing terminal C to capture packets from the main system server A and provides the captured packets to the standby system server B in the same sequence pattern as that of the main system server A.
FIG. 23 depicts another example of relative performance evaluation processing for a conventional main system server and a standby system server. In the example depicted in FIG. 23, the main system server A is located in Osaka, the standby system server B is located in Tokyo, and the testing terminal C is provided in both Osaka and Tokyo. In this case, the test conductor performs packet communication between the testing terminal C and the main system server A in Osaka and at the same time interval as the main system server A, performs packet communication between the testing terminal C and the standby system server B in Tokyo, whereby relative performance evaluation of the main system server A and the standby system server B is performed.
Nonetheless, if the main system server A and the standby system server B are at different locations, the difference (distance and positive correlation) in the round trip times (RTT), i.e., the round trip delay times, of the main system server A and the standby system server B affects the processing interval (processing load) of the main system server A and the standby system server B. In other words, the interval of packet transmission/reception at the standby system server B is comparatively longer than that at the main system server A. Consequently, performance evaluation using equivalent loads cannot be performed, inviting deterioration in the quality of the performance evaluation.
Further, a packet may be sent after analysis of the information included in the acknowledgment packet of a packet previously transmitted, such as in the case of 3-way handshake, inclusion of a cookie in a packet, etc. In such cases, since transmission to the standby system server B requires waiting for an acknowledgment packet to be received for the packet previously transmitted, the packet transmission/reception interval of the standby system server B becomes comparatively longer than that of the main system server A. Consequently, performance evaluation using equivalent loads cannot be performed, inviting deterioration in the quality of the performance evaluation.